The purpose of the application is to obtain funding to replace the existing Philips 400 TEM in the shared-user EM Center in the Department of Anatomy and Cell Biology with a state-of-the-art TEM, the JEOL 1230. The Philips 400 TEM was purchased with NSF funds in 1979 and has served over 40 different researchers over the last 23 years, but this machine is presently unreliable and outdated. Since the acquisition of the Philips 400 TEM, significant technical advances have occurred in transmission electron microscopes which include ease of use and extended capabilities like digital image recording and ultracryo-microscopy. The new TEM will be housed in a 1789 sq. ft. laboratory dedicated to electron microscopy, supervised by a full-time faculty member, Dr. Vincent Gattone and managed by a full-time, highly qualified EM specialist, Ms. Caroline Miller. The microscope will be available to all investigators within the Indiana University-Purdue University campus at Indianapolis which includes Schools of Dentistry, Medicine, Science and Engineering & Technology. However, the majority of the research projects will come from ten (10) laboratories. These investigators have been identified as "major users" of the new instrument. Dr. Robert Bacallao will employ a variety of biochemical assays for protein sorting, immunohistochemical and ultrastructural analyses of Golgi complex dysfunction following ischemic injury. Dr. Andrew Evan will use imunohistochemical and digital imaging to precisely correlate sites of renal crystal deposition with known inhibitors of stone formation. Dr. Loren Field will use TEM to correlate structural changes in cardiomyocytes after specific pathological conditions. Dr. Lincoln Ford requires digital TEM images to accurately measure changes in smooth muscle thick filaments during contractility. Dr. Susan Gunst needs digital TEM images to evaluate the cellular mechanisms that regulate the response of airway smooth muscle to mechanical forces generated during breathing. Dr. James McAteer's studies require the high resolution of the TEM to detect subtle damage to the vascular endothelium induced by shock wave lithotripsy. Dr. Bruce Molitoris will employ immunohistochemistry to determine the cellular, biochemical and molecular mechanisms responsible for ischemia induced membrane changes. Dr. Carrie Phillips will use immunogold EM to evaluate the cellular localization of inversin protein in the inv mutant mouse model of PKD. Dr. Zao Xu will use TEM to investigate the nature of cell death, e.g. necrosis or apoptosis, in neostriatum of the rat after transient global schemia. Dr. Richard Gregory will employ immunohistochemistry to examine the role of a Streptococcus mutans 65 kDa fimbrial protein binding as a mechanism for the induction of dental carries.